#abre_panel{ 
  position: absolute; 
  background-image: url(../img/menu_btn.png); 
  background-repeat: no-repeat; 
  width: 50px; 
  height: 20px; 
  box-shadow: none; 
  background-color: transparent !important; 
  border: none; 
  left: -5px; 
  top: 0; 
  margin-top: 6px !important; 
} 
